module Markaby::BuilderTags

def enable_html5! 

def enable_html5!
  raise NotImplementedError, "Deprecated! Call self.tagset = Markaby::HTML5"
end

def head(*args, &block)

set to text/html; charset=utf-8.
Builds a head tag. Adds a meta tag inside with Content-Type 
def head(*args, &block)
  tag!(:head, *args) do
    tag!(:meta, "http-equiv" => "Content-Type", "content" => "text/html; charset=utf-8") if @output_meta_tag == "xhtml"
    tag!(:meta, "charset" => "utf-8") if @output_meta_tag == "html5"
    instance_eval(&block)
  end
end

def html5(attrs = {}, &block)

Builds an html tag with HTML5 doctype instead. 
def html5(attrs = {}, &block)
  self.tagset = Markaby::HTML5
  html5_html(attrs, &block)
end

def html5_html(attrs = {}, &block) 

def html5_html(attrs = {}, &block)
  declare!(:DOCTYPE, :html)
  tag!(:html, @root_attributes.merge(attrs), &block)
end

def html_tag(sym, *args, &block)

could lead to invalid XHTML.
If the @auto_validation setting is on, this method will check for many common mistakes which

for this method.
to calling html_tag(:div). All HTML tags in Markaby's list are given generated wrappers
Every HTML tag method goes through an html_tag call. So, calling div is equivalent 
def html_tag(sym, *args, &block)
  if @auto_validation && @tagset.self_closing.include?(sym) && block
    raise InvalidXhtmlError, "the `#{sym}' element is self-closing, please remove the block"
  elsif args.empty? && !block
    CssProxy.new(self, @streams.last, sym)
  else
    tag!(sym, *args, &block)
  end
end

def xhtml_frameset(attrs = {}, &block)

Builds an html tag with XHTML 1.0 Frameset doctype instead. 
def xhtml_frameset(attrs = {}, &block)
  self.tagset = Markaby::XHTMLFrameset
  xhtml_html(attrs, &block)
end

def xhtml_html(attrs = {}, &block) 

def xhtml_html(attrs = {}, &block)
  instruct! if @output_xml_instruction
  declare!(:DOCTYPE, :html, :PUBLIC, *tagset.doctype)
  tag!(:html, @root_attributes.merge(attrs), &block)
end

def xhtml_strict(attrs = {}, &block)

Builds an html tag with XHTML 1.0 Strict doctype instead. 
def xhtml_strict(attrs = {}, &block)
  self.tagset = Markaby::XHTMLStrict
  xhtml_html(attrs, &block)
end

def xhtml_transitional(attrs = {}, &block)

:lang => "en".
are prepended. Also assumes :xmlns => "http://www.w3.org/1999/xhtml",
Builds an html tag. An XML 1.0 instruction and an XHTML 1.0 Transitional doctype 
def xhtml_transitional(attrs = {}, &block)
  self.tagset = Markaby::XHTMLTransitional
  xhtml_html(attrs, &block)
end